The present invention relates to apparatus for providing a stringed musical instrument with the capability of operating on multiple tonal scales.
Stringed instruments such as guitars, banjos, electric bass guitars, and the like typically have a fingerboard underlying the strings which contains a plurality of fixed non-movable frets. The individual playing the instrument uses his fingertips to press the strings against the frets on the fingerboard to change the effective length of the string and thereby select the tone generated when the string is vibrated. The location of the frets on the fingerboard provides a fixed set of tones which can be generated on any one instrument. The available tones from such an instrument is called its tonal scale.
The music which can be played on a stringed instrument having fixed frets is limited to the specific tones included in the tonal scale of that instrument. This limitation is acceptable for music which is written specifically for an instrument having a particular tonal scale, but the instrument cannot be used to play other forms of music which require tones not included in the instrument's tonal scale. Instruments are available which have movable frets, such as the sitar. However, the operation of the movable frets in such an instrument is quite difficult and the incorporation of movable frets in standard fixed fret instruments is impractical.
The present invention provides a stringed musical instrument with fixed frets with the capability of employing more than one tonal scale. At least two fretted fingerboards are provided with frets located at different relative positions on the respective fingerboards. A transversely opening groove is formed on the instrument beneath and parallel to the strings. On the underside of each fingerboard, a corresponding groove is provided which opens transversely with respect to the fingerboard. Each of the fingerboards can be mounted to the instrument when desired by engaging the groove on the selected fingerboard with the corresponding groove on the instrument. A mechanism is provided for forcing the grooves together so that the fingerboard is secured to the instrument in a releasable fashion.
By providing a plurality of fingerboards with frets located in different positions, each fingerboard being individually attachable to the instrument, a stringed instrument with fixed frets can be played on different tonal scales, greatly increasing the flexibility of the instrument and allowing it to play different types of music. With the apparatus of the present invention, the selected fingerboard can readily be located in place on the instrument by engaging the respective transverse grooves on the fingerboard and the instrument. The grooves are then forced together to secure the fingerboard to the instrument. When a different tonal scale is desired, the fingerboard on the instrument can readily be detached therefrom and an alternate fingerboard secured to the instrument.
A critical problem in mounting a fingerboard to a stringed instrument in a detachable fashion is the vibration of the fingerboard if it is not securely attached to the instrument. In stringed instruments, the quality of the instrument depends on its ability to transfer sound from the neck of the instrument on which the fingerboard is located to the body. Any vibration which occurs in the instrument at the neck, such as would be caused by a fingerboard improperly secured thereto, causes a loss of sound energy, particularly at high frequencies. This loss of energy flattens the sound and may degrade its quality of such an extend that the instrument is an undesirable alternative to standard fixed fretted instruments.
The present invention provides a mechanism for mounting the removable fingerboard to the instrument by engaging corresponding grooves on the instrument and the fingerboard respectively. The grooves themselves are forced together to secure the fingerboard to the instrument, minimizing and virtually eliminating vibration of the fingerboard relative to the instrument which would detract from the quality of the instrument. As a result, stringed instruments can be provided with multiple tonal scales without sacrificing their quality.
The novel features which are characteristic of the invention, as to organization and method of operation, together with further objects and advantages thereof will be better understood from the following description considered in connection with the accompanied drawings which preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawings are for the purposes of illustration and description only and are not intended as a definition of the limits of the invention.